| 摘要 |
PURPOSE:To markedly reduce a frictional load generated at the time of moving and enable to drive by a cell for a long period of time, by moving a thermal head holding part in rolling contact with a carriage guide shaft concurrently with movement of a carriage. CONSTITUTION:When printing, a cam follower 28 and a cam 29 do not make contact with each other, a main guide shaft 20 is rotated by a spring 30 through a cam lever 27, the holding part 22 presses the thermal head 6 against an elastic pad 7, and the carriage 21 is moved with the progress of printing. On the other hand, when returning the carriage 21, the cam 29 makes contact with the cam follower 28 to rotate the main guide shaft 20, and releases the thermal head 6 from the pressed condition through engagement between notched parts 20a, 20b of the guide shaft 20 and ball bearings 23-25. This movement of the carriage 21 is guided through rolling contact between the ball bearings 23-25 of the holding part 22 and the main guide shaft 20, whereby the frictional load is markedly reduced, consumption of electric power for driving is reduced, and it is enabled to drive by a cell for a long period of time. |
